Known prior art methods of sealing wires and/or terminals include the use of grommets or other similar compression seals, and the use of heat shrinkable sealing sleeves. Other prior art methods use articles containing grease. However, greases lack any type of structural network, and this results in the greases generally being viscous and flowing when subjected to temperature cycling, thereby providing a relatively unstable means for protecting the terminals and/or wires. Epoxies and other adhesives have also been used, but they are also disadvantageous in that reentry is difficult.
Gel grommets are an effective method of sealing close center-to-center spaced connectors. A single sealing member may be employed in an application for which the number of connections is not known prior to its selection. For example, such a connector design may be employed to seal the connectors for various "options" in an automobile. At the time of selection of the sealing member, the number of options the end purchaser will select is unknown. For this reason, and also to simplify production, it is not desirable to require different sealing members based upon the number of options selected.
U.S. Pat. No. 5,588,856 entitled "Sealing Member and Methods of Sealing" issued to Collins et al and assigned to the assignee of the present invention, which is hereby incorporated by reference for all purposes, discloses a gel grommet having a layer of gel disposed between two constraining layers. The constraining layers are preferably a compressible foam which accommodates volume changes of the gel. Such gel grommets are cost-effective, re-enterable a limited number of times, enable miniaturization, and thus provide a competitive advantage in the automotive marketplace. However, particles from the material of the constraining layers may become lodged between the contacts during insertion or removal, causing interference with the connection. Additionally, the sealing material can be torn or otherwise damaged upon insertion and removal of the contacts.
U.S. Pat. No. 5,529,508 entitled "Sealing Member" issued to Chiotis et al, having a common inventor with the present invention, and commonly assigned with the present application, which is hereby incorporated by reference for all purposes, discloses a gel grommet having a layer of sealant positioned longitudinally between two constraining layers. The constraining layer is preferably a gel having a Voland hardness greater than the Voland hardness of the sealant. This configuration does not allow particles to contaminate the connection of substrates or wires inserted through the sealing member. Insertion of the substrate or wire through the sealing member may, however, tear or otherwise damage the sealing material such that it cannot be removed and reinserted without compromising seal integrity after the seal has been in use for a significant period of time.